so a guy over on yaris world has successfully swapped prius pistons into his car with no adverse effects as of yet. here is the thread:
http://www.yarisworld.com/forums/showthread.php?t=40646

 

i'm not joining that site just to see the pics

 

i cant see the pics either but its a GREAT read for anyone wanting to get some decent power out of the 1nzfe

 

Oh ya, planning on doing this in the spring. Nice thing about the way our engine sits, just pull the head and oil pan but since its gonna be torn apart I'm gonna go ahead and replace the timing chain. I am certain our engines will hold up to the compression reliably without failure. Also with that kind of compression we would be running VERY close to blitz SC numbers since the superchargers add parasitic drag to engines, and the nice thing is that those numbers would be essentially be ON all the time which makes me :D. With these, this is when all the intake and exhaust mods come together and would probably benefit from a cat back versus an axle back. The pics are of the pistons comparing them uninstalled and installed is all. Still waiting for that guy to do his dyno.

 

Still no update to the guys thread who installed these in hiw yaris, hope everything is still working good with him. Also wanted to share some power estimates. After doing some reading on the web with a guy from indonesia and competes competetively in their track motorsports with his 1nzfe he was saying that he increased his compression from 10.5 to 11 and estimated 4-7% increase since he could feel a difference. So going by his estimation on the conservative side by stock crank horse power that would be 4% power increase per .5 increase in compression totaling 20% increase in power over stock baseline crank rated numbers to 127hp. Then estimate in other bolt ons such as CAI, throttle body, manifold, header, catback, pulleys, etc. It would be upwards of 150ish bhp. By that standard alone and factor parasitic draivetrian loss of 20%, again conservative, that would put me around 128 whp. If these estimates are off or factoring things I shouldn't please correct me. 128whp is above most blitz numbers and moving close to turbo numbers. To say I am excited is an understatement at this point.

 

I think don did a Prius piston/head swap and added some rods to the mix. I don't know if he posted anything on it but I would love to read it if he did.